Introduction to the Elmdene QST‑RD and its key features
Elmdene QST‑RD — compact Grade 2 surface magnetic door contact for wired intruder systems.The QST‑RD is a surface‑mount wired door contact designed for everyday door and window intrusion detection in domestic and light commercial environments. Its compact footprint, screw‑terminal termination and optional integral end‑of‑line (EOL) resistor options make it a practical choice for installers who need a reliable, easy‑to‑fit contact that meets Grade 2 security expectations.
Key features at a glance:
- Grade 2 security rating suitable for domestic and light commercial intruder alarm installations.
- Surface‑mount design with compact dimensions (approx. 70 × 17 × 15 mm).
- 20 mm standard operating gap between magnet and contact.
- Screw‑terminal termination; optional integral EOL/shunt resistor options (colour‑coded) for convenient wiring.
- Available in white or brown with an ABS plastic body and CE marking noted on distributor listings.
Detailed specifications and benefits
The QST‑RD’s specification profile is focused on practical installation and reliable operation. The contact is built as a surface‑mount magnetic switch, using a small magnet and a sealed contact body to detect opening and closing of doors and similar openings. Although installers should consult the official datasheet for full electrical ratings and environmental limits, the model’s primary specifications are summarised below.
- Model: QST‑RD
- Product type: Surface‑mount magnetic door contact (wired)
- Security grade: Grade 2
- Operating gap: 20 mm (standard)
- Termination: Screw terminals for easy cable connection
- Dimensions: Approx. 70 × 17 × 15 mm (compact footprint)
- Material: ABS plastic housing
- Colours: White (also available in brown)
- Mount type: Surface mount (suitable for door frames, windows and similar applications)
- Resistors: Integral EOL/shunt resistor options (colour‑coded) for FSL or double‑pole wiring
- Certifications: CE indicated on distributor listings
- Warranty: Typical distributor listing: 5 years (check manufacturer terms)
- Compact size: The small footprint (approx. 70 × 17 × 15 mm) allows installation on narrow frames and tight locations where larger contacts won’t fit.
- Screw‑terminal wiring: Simple screw terminals speed up installation and reduce the need for additional terminal blocks or soldering on site.
- EOL resistor options: Integral, colour‑coded resistor choices simplify compliance with modern alarm panel circuits that require end‑of‑line supervision without having to add external resistors.
- Grade 2 suitability: Meets the performance expectations for many residential and light commercial systems where Grade 2 is specified by installers or project requirements.
- Choice of colours: White or brown options mean the contact can be matched to common door and frame finishes for a cleaner aesthetic.
Use cases and scenarios where the QST‑RD excels
The QST‑RD is well suited to a range of everyday intrusion detection tasks. Typical use cases include:
- Residential front and back doors: The compact, surface‑mount form factor is ideal for timber or composite door frames where recessed contacts are impractical or where retrofit installations are required.
- Windows and patio doors: Where a low‑profile, visible contact is acceptable, the QST‑RD provides reliable detection with a convenient 20 mm operating gap that tolerates minor alignment variations.
- Light commercial premises: Small offices, retail outlets, and non‑critical internal doors that require Grade 2 detection can use the QST‑RD as a cost‑effective solution.
- Refurbishment and retrofit projects: The surface‑mount design removes the need for routing cavities or drilling deep pockets, cutting installation time and preserving frame integrity.
- Systems requiring supervised circuits: With integral EOL resistor options, the contact integrates smoothly into alarm panels that require supervision without additional components.
Because it is a wired contact with screw‑terminal connections, the QST‑RD is best used where a wired alarm infrastructure is preferred or already in place. It is not a wireless contact, so it is not intended for installations where radio‑linked devices are required.
Comparisons with similar products in the market
When evaluating the QST‑RD against comparable door contacts, several factors commonly influence the choice: security grade, mounting style, size, termination type and available supervision options. Here’s how the QST‑RD stacks up against common alternatives.
- Surface‑mount (QST‑RD): Easier to install, ideal for retrofits, no routing required. More visible and slightly larger profile compared with recessed options.
- Recessed contacts: Concealed and more discreet, often preferred where aesthetics are critical. Typically require routing or drilling in the frame and door, which can add labour.
- Grade 2 (QST‑RD): Suitable for most domestic and light commercial applications where recognized standard levels of performance are needed.
- Grade 1: Often used for low‑risk or very basic alarm needs; may not meet commercial project specifications.
- Grade 3 and above: Used for higher‑security environments; usually more robust and sometimes more expensive than Grade 2 products.
- Screw terminals (QST‑RD): Quick on‑site wiring, easily serviced and modified. Preferred by many installers for speed and reliability.
- Soldered/pigtail: Can offer a smaller profile but often requires more skill and time to install or replace.
- Wired (QST‑RD): Reliable, no battery replacement, and typically lower per‑unit cost for large installations. Requires cabling infrastructure.
- Wireless: Best for locations where running cables is impractical; adds battery maintenance and usually a higher component cost per point.
Customer feedback and installer observations
Official customer testimonials are not provided here, but common installer observations and anonymised, representative feedback from installers who prefer this type of product include:
- "Compact and easy to fit — worked well on tight wooden frames where a recessed contact wasn’t an option."
- "The colour‑coded EOL options saved time on site and reduced the need to carry extra resistors."
- "Solid screw terminals make for a reliable termination that holds up during servicing."
These representative comments reflect typical advantages reported by technicians using compact, surface‑mount Grade 2 contacts. For formal reviews or customer testimonials, check with retailers or distributor pages where buyers sometimes leave product ratings.
Conclusion: Why the Elmdene QST‑RD is a strong choice
The Elmdene QST‑RD is a practical, purpose‑built surface‑mount door contact that balances compact size, straightforward installation and Grade 2 security performance. Its screw‑terminal design and integral EOL resistor options make it particularly attractive for installers and resellers who need reliable wired contacts that are quick to fit and integrate into supervised alarm circuits.
For projects where recessed mounting is impractical, and where a Grade 2 level of detection is specified, the QST‑RD delivers a cost‑effective, tidy solution available in two common colours to help maintain neat aesthetics. Typical distributor listings note a 5‑year warranty and CE marking is indicated; installers should always confirm the latest datasheet and warranty terms with the manufacturer or distributor prior to purchase.
Suggested retail pricing guidance: £9.99 (suggested price) — check current distributor listings for bulk or trade pricing. For full electrical ratings, operating temperature and installation guidance, consult the official Elmdene QST‑RD datasheet/installation manual and ensure installation is carried out in accordance with local regulations and best practice.
